https://orcid.org/0000-0002-9332-0913
Abstract
Anomalous left coronary artery from the pulmonary artery is a rare congenital coronary anomaly commonly associated with severe but reversible left ventricular dysfunction. We present an anomalous left coronary artery from the pulmonary artery case of persisting left ventricular failure with inability to wean off the ventilator and inotropes after successful coronary reimplantation, in whom pulmonary artery banding enhanced myocardial recovery.
CASE PRESENTATION
A 10-month-old infant was admitted because of failure to thrive, tachypnoea and excessive sweating during feeding. Echocardiography showed severe left ventricle (LV) dilatation [LV end-diastolic diameter (EDD) 50 mm; Z-score +11] (Fig. 1 and Videos 1–3), grade II mitral regurgitation (MR) and poor systolic function (EF 23–28%). The diagnosis of anomalous left coronary artery from the pulmonary artery (ALCAPA) was made by transthoracic echocardiography. The next day, coronary reimplantation was performed successfully and weaning of cardiopulmonary bypass (CPB) was achieved with epinephrine and levosimendan, the chest was closed at the end of the procedure.
Echocardiographic evolution on four-chamber and short axis views.
Pre-operative subcostal.
Pre-operative mitral valve insufficiency.
Pre-operative short axis LV.
Two attempts at ventilatory weaning on postoperative day (POD) 6 and 16 proved unsuccessful with need for reintubation. On POD 21, there were still remnant clinical signs of circulatory failure, a high inotropic need (combination of milrinon, epinephrin and norepinephrin) and a persistently severely dilated LV (LV EDD 53 mm; Z-score +12.3) with poor LV function and MR grade II on cardiac ultrasound. As echocardiographic imaging of the reimplanted left coronary artery (LCA) showed adequate non-obstructed coronary flow while slow ventricular recovery was expected, no additional imaging was performed at this time.
Considering the predominant LV dysfunction and preserved RV function, pulmonary artery banding (PAB) was forwarded as a valid option to aid weaning from inotropic and ventilatory support. On POD 27, PAB was performed after preoperative cardiac function optimization with levosimendan. PAB was done with a polytetrafluorethylene strip (Gore-Tex, Gore & Associates, Newark, Delaware) of 5 mm height, fixed by 3–4 consecutive polypropylene 6.0 U-stitches at interval distances per 3 mm.
The tightness of the banding was guided by transoesophageal echocardiographic evaluation of ventricular dimensions and the position of the interventricular septum. At an RV pressure of 55 mmHg (for a systemic pressure of 80 mmHg), a left-sided shift of the interventricular septum was obtained without compromising circulation. The patient returned to ICU with closed chest and need of limited haemodynamic support. Recovery from the PAB was uneventful and inotropics could be completely stopped within 4 days. Finally, respiratory support was withdrawn on day 15 after PAB (42 days after initial repair). On echocardiography, LV systolic function remained poor and grade II mitral regurgitation was unchanged (Videos 4–6).
Post-banding 4-chamber view.
Post-banding mitral valve insufficiency.
Post-banding short axis.
During the follow-up progressive recovery of systolic LV function and a decrease in LV dimensions ensued, accompanied by gradual clinical improvement (Fig. 2). After 1 year, the child was doing well, showing a complete recovery of LV function (LV EDD Z-score −1.6 and EF 73%) and no mitral regurgitation at echocardiography (Videos 7 and 8). Since the gradient across the banding had increased to 80 mmHg, partial de-banding was performed with a 10-mm high-pressure balloon, alleviating RV pressure-overload (RV end-systolic pressure 55 mmHg and gradient across the banding of 35 mmHg). Echocardiographic evaluation showed normalization of the septal position while preserving normal LV function. Further follow-up will determine whether repeat interventions for full debanding are necessary.
Evolution of left ventricle end-diastolic dimension (as Z-score). EDD: end-diastolic diameter; LV: left ventricle; POD: postoperative day(s).
Pre-debanding 4 chamber.
Pre-debanding short axis.
DISCUSSION
After ALCAPA repair, recovery of systolic LV function typically takes several months, in some cases even up to 2 years [1–3]. Although temporary mechanical circulatory support (by ECMO or LVAD) is indicated in patients with ALCAPA who cannot be weaned off bypass [1, 2], in the child presented here 3 weeks had already passed since corrective surgery and initial successful weaning off CPB but at the cost of persisting clinical heart failure and need for sustained inotropic and ventilatory support. Thus, a bridging-solution enhancing recovery was needed, taking into account that a longer-term mechanical heart support in such small infant is associated with a considerably high complication rate [4]. Based on the successful use as a bridge to recovery in LV dilated cardiomyopathy (DCM), PAB has recently been proposed as an interesting adjunct in LV DCM associated with congential heart disease [5].
Since the recovery of LV function was expected with time and RV function was intrinsically preserved, our patient was thought to be a good candidate for PAB. Despite that echocardiographic LV function improvements during the first days after PAB were not impressive, the clinical benefit was clear by gradual weaning of inotropes and ventilatory support in the following days. The combination of pressure loading of the RV and improving the LV function efficacy through restoring the LV geometry related to the septal shift enabled to surpass the critical phase of inotropy-dependent heart failure. Although gradual ventricular recovery is to be expected, the acute clinical improvement within a few days suggested a strong correlation with the intervention. Further recovery resulted in complete normalization of LV dimensions after 1 year.
This case illustrates that PAB can be a helpful adjunct to the weaning off inotropic support and/or mechanical ventilation in dilated LV cardiomyopathy, regardless of its aetiology and provided that RV function is normal. To our knowledge, this is only the second time PAB is used successfully as a bridge to recovery after ALCAPA repair [5], suggesting PAB as a less-invasive alternative than mechanical LV assist devices, to enhance delayed myocardial recovery after ALCAPA repair.
CONCLUSION
In a case of persistent circulatory failure due to LV DCM after corrective surgery for ALCAPA, PAB may be considered a helpful adjunct to enhance ventilatory and inotropic weaning. Gradual myocardial recovery resulted in further resolution of clinical symptoms, with the echocardiographic normalization of LV function after 1 year.
Funding
The authors did not receive support from any organization for the submitted work. Informed consent was obtained from legal guardian.
Conflict of interest: none declared.
Reviewer information
European Journal of Cardio-Thoracic Surgery thanks Katarzyna Januszewska, Philippe Grieshaber and the other, anonymous reviewer(s) for their contribution to the peer review process of this article.
